SR_for_LCD.pseudo

/***Module for writing to shift register connected to the LCD monitor***/

initialize module leve variables
define ALL_BITS offset variable as 0xff<<2

/**************************************************************
Function: SR_Init_LCD
Takes: nothing
Returns: nothing
Purpose: initializes the Tiva pins that are used to control the shift register
/*************************************************************/
SR_Init_LCD
	Initialize port F
	Initialize bit 0
	Initialize bit 1
	Initialize bit 2
	Set Data Line Low
	Set Shift Clock Low
	Set Register Clock High
end

/**************************************************************
Function: SR_Write_LCD
Takes: 8 bit integer
Returns: nothing
Purpose: writes input 8 bit integer to the 8 outputs (Q0-Q7) of the shift register
/*************************************************************/
SR_Write_LCD
	pass input param to static variable ShiftRegisterImage
	Set STCP low
	Shift data onto serial data line while pulsing shift clock
	loop 8 times
		if LSB of input param is high
			set bit 0 high		
		else 
			set bit 0 low
		endif
		Set SHCP hi
		Set SHCP low
		Shift NewValue right 1 bit	
	Set STCP hi
end

/**************************************************************
Function: SR_GetCurrentRegister_LCD
Takes: nothing
Returns: 8 bit integer
Purpose: allows other modules to check the last integer that was written to the shift register
/*************************************************************/
SR_GetCurrentRegister_LCD
	return variable ShiftRegisterImage
end